Change the position of the maps map by clicking

Question

I want to change the position of the marker of the maps by clicking on the screen of the Smartphone, in my code instead of changing the position it creates several markers.

below the main code Activity

package com.t2ti.localizacao;

import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.widget.Toast;

import com.google.android.gms.maps.CameraUpdate;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;

public class MapsActivity extends FragmentActivity {

    private GoogleMap mMap; // Might be null if Google Play services APK is not available.
    private double latitude;
    private double longitude;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_maps);

        latitude = getIntent().getDoubleExtra("latitude", 0);
        longitude = getIntent().getDoubleExtra("longitude", 0);


        setUpMapIfNeeded();


    }

    @Override
    protected void onResume() {
        super.onResume();
        //setUpMapIfNeeded();
        //configura o zoom do mapa
        LatLng local = new LatLng(latitude, longitude);
        CameraUpdate update = CameraUpdateFactory.newLatLngZoom(local, 15);
        mMap.animateCamera(update);

        mMap .setOnMapClickListener( new GoogleMap.OnMapClickListener() {
            @Override
            public void onMapClick (LatLng latLng) {
                MarkerOptions options = new MarkerOptions() ;
                options.position( latLng ) ;
                mMap .addMarker( options ) ;

                //mMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)).title("Marker"));
            }
        });

    }

    /**
     * Sets up the map if it is possible to do so (i.e., the Google Play services APK is correctly
     * installed) and the map has not already been instantiated.. This will ensure that we only ever
     * call {@link #setUpMap()} once when {@link #mMap} is not null.
     * <p/>
     * If it isn't installed {@link SupportMapFragment} (and
     * {@link com.google.android.gms.maps.MapView MapView}) will show a prompt for the user to
     * install/update the Google Play services APK on their device.
     * <p/>
     * A user can return to this FragmentActivity after following the prompt and correctly
     * installing/updating/enabling the Google Play services. Since the FragmentActivity may not
     * have been completely destroyed during this process (it is likely that it would only be
     * stopped or paused), {@link #onCreate(Bundle)} may not be called again so we should call this
     * method in {@link #onResume()} to guarantee that it will be called.
     */
    private void setUpMapIfNeeded() {
        // Do a null check to confirm that we have not already instantiated the map.
        if (mMap == null) {
            // Try to obtain the map from the SupportMapFragment.
            mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map))
                    .getMap();
            // Check if we were successful in obtaining the map.
            if (mMap != null) {
                setUpMap();
            }
        }
    }

    /**
     * This is where we can add markers or lines, add listeners or move the camera. In this case, we
     * just add a marker near Africa.
     * <p/>
     * This should only be called once and when we are sure that {@link #mMap} is not null.
     */
    private void setUpMap() {
        mMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)).title("Marker"));
    }


}

Answer 1

I was able to put the clear function of the Googlemap variable mmap at the beginning of the map onclick method.

example below:

  mMap .setOnMapClickListener( new GoogleMap.OnMapClickListener() {
        @Override
        public void onMapClick (LatLng latLng) {
            //função clear
            mMap.clear();
            MarkerOptions options = new MarkerOptions() ;
            options.position( latLng ) ;
            mMap .addMarker( options ) ;

            //mMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)).title("Marker"));
        }
    });

Answer 2

You must use Cameraupdate to make these programmatic map movements.

To do this, first calculate the limits of all markers as follows:

LatLngBounds.Builder builder = new LatLngBounds.Builder();
for (Marker marker : markers) {
    builder.include(marker.getPosition());
}
LatLngBounds bounds = builder.build();

Then get a motion object using Factory CameraUpdateFactory

int padding = 0; // deslocamento das bordas do mapa em pixels
CameraUpdate cu = CameraUpdateFactory.newLatLngBounds(bounds, padding);

Finally move the map:

googleMap.moveCamera(cu);

Or if you want an animation:

googleMap.animateCamera(cu);